Protesters demonstrate following a New York grand jury's decision not to indict a police officer in the chokehold death of Eric Garner on December 3, 2014 in Oakland. (Elijah Nouvelage/Getty Images)
Many of the thousands of protesters who marched in San Francisco, Berkeley and Oakland this past week are not old enough to have seen earlier social causes championed on those same streets.
The protesters were mostly young -- and angry over recent grand jury decisions not to prosecute two police officers involved in the deaths of unarmed black men in New York and Missouri. They chanted phrases like "Black Lives Matter" and "I Can't Breathe," a reference to Eric Garner's final words on Staten Island before he died after a police chokehold.
Among those in the crowd Sunday night was 21-year-old Carisma Lyday, who said she was there because she has older and younger brothers.
"It's really, it hits a soft spot for me because I'm African-American, Lyday said. "So, you know this is personal to us."
These recent demonstrations come 50 years after another famous protest, the Free Speech Movement at UC Berkeley. In December of 1964, activist Mario Savio gave a memorable speech on the steps of Sproul Hall, railing against the university administration.
"And you've got to put your bodies upon the gears, and upon the wheels, upon the levers, upon all the apparatus and you've got to make it stop," Savio shouted in the most famous part of his speech.
It's easy to forgot how controversial and divisive those student protests were. But in 1966, Ronald Reagan ran against them on a law-and-order platform, defeating incumbent Gov. Pat Brown.
The Free Speech Movement rolled right into the Vietnam War protests in the late '60s and '70s. Among the student organizers then wasJean Quan, who's now mayor of Oakland.
" I think in the '60s when we did civil disobedience, we took over the president's office, etc., we expected to get arrested," Quan said this week in a phone conversation. "It was part of, you know, the whole nonviolent movement at that time."
In other words, says Quan, getting arrested was the whole point of those protests. Putting on her mayor's hat, Quan says she worried that people would get hurt when protests spilled onto Interstate 80 and Highway 24.
"You know, I get that you do it for attention. But if you keep doing it," Quan adds, "I think it loses its power."
She also says that media today give too much coverage to the few incidents of violence.
"At the end of these demonstrations, there's always probably less than a dozen people who break a few windows in town," Quan complains. "And you have the impression that my city has burned down."
Berkeley also gave birth to the anti-apartheid movement in 1984.
Steve Masover was a leader in the Campaign Against Apartheid -- aimed at getting UC to divest from companies doing business in South Africa. He said the diversity of actions taken by anti-apartheid groups was key to their success.
"I don't think that any one tactic, any one approach could have made a difference in and of itself," he says.
Masover remembers that, like today, some of the tactics used by the anti-apartheid campaign back then were also criticized.
"The sit-in, the shantytown protests, the ship blockade," Masover recalls. "Those were regarded by many as fairly radical, that got a lot of press attention. They generated a lot of energy. "
During the recent protests in Berkeley and Oakland, nothing has divided feelings more than the few instances of vandalism. What struck Zachary Murray, a young black activist in Oakland, is that too often these protests were led by Caucasian men.
"With sort of like a lot of the violence, the fires,the broken windows that we've seen, those folks don't represent the folks who really had the rage right now, right, the folks who really had the anger," Murray says at his home near the MacArthur BART station in Oakland.
"They're taking advantage of real rage and real anger and really characterizing a movement in a way that they should not be."
So last weekend, Murray and other young African-American activists went to upscale cafes and restaurants in Oakland, reciting the names of black men killed by police.
After making a short announcement saying what they were about to do, the group began its presentation as surprised diners watched.
"Jamel Canney, 13 years old. Ashe! Kenneth Harding, 19 years old. Ashe! Raheem Brown, 20 years old. Ashe!," and so on.
Each name was followed by the chant "Ashe," an African phrase meaning roughly "so it is."
The action was organized on social media, including Twitter, hashtag Black Brunch. One of the organizers was 23-year-old Oakland resident Wazi Davis. The goal: reach people who can easily avoid thinking about police treatment of black men.
"And we're saying, no, you are going to stop eating right now, you're going to stop whatever transaction it is you're putting in at the cash register, you're going to sit here and you're going to listen to us read the names of our brothers and sisters," Davis says.
The organizers of Black Brunch are planning other actions -- they won't say when they'll be or what will be on the menu.
Stanford Professor Doug McAdam studies political movements. He says controversial protest is in our DNA, going back to the Boston Tea Party. And like it or not, violence is often part of it -- including now, in the reaction to failure to prosecute police who kill unarmed black men.
"We can deplore the violence at the edges of the movement, and we should," McAdam says. "But the idea that somehow we're gonna get change on these critical issues by only using institutional means is, I think, a fallacy."
The question now is how committed this new generation of protesters is to solving long-standing problems between police and communities of color.